scholarly journals Overview of nitrogen oxide reactions during fossil fuel combustion in the atmosphere

2020 ◽  
Vol 10 (2) ◽  
pp. 103-108
Author(s):  
Sveta Cvetanović
Keyword(s):  
Nitrogen Oxides ◽  
Nitrogen Oxide ◽  
Fossil Fuel ◽  
Theoretical Models ◽  
Fuel Combustion ◽  
Chemical Processes ◽  
Pollutant Emissions ◽  
Fossil Fuel Combustion ◽  
Pollutant Formation ◽  
Factors Influencing

This paper discusses the reactions of formation and decomposition of nitrogen oxides during fossil fuel combustion and in the atmosphere. Information about the chemical processes of pollutant formation and decomposition is the basis for the development of theoretical models of pollutant emissions. The information also provides a clearer picture about the primary factors influencing emissions. Nitrogen oxides are pollutants that damage human health, living and nonliving nature, and material property.

Response : Sulfur Mobilization as a Result of Fossil Fuel Combustion

Science ◽  
1972 ◽  
Vol 175 (4027) ◽  
pp. 1279-1279
Author(s):  
K. K. Bertine ◽  
Edward D. Goldberg
Keyword(s):  
Fossil Fuel ◽  
Fuel Combustion ◽  
Fossil Fuel Combustion

scholarly journals Seasonal changes in Fe species and soluble Fe concentration in the atmosphere in the Northwest Pacific region based on the analysis of aerosols collected in Tsukuba, Japan

2013 ◽  
Vol 13 (15) ◽  
pp. 7695-7710 ◽  
Author(s):  
Y. Takahashi ◽  
T. Furukawa ◽  
Y. Kanai ◽  
M. Uematsu ◽  
G. Zheng ◽  
...  
Keyword(s):  
Fossil Fuel ◽  
Fuel Combustion ◽  
Anthropogenic Sources ◽  
Anthropogenic Activity ◽  
Northwest Pacific ◽  
Pacific Region ◽  
Fossil Fuel Combustion ◽  
Factors Affecting ◽  
X Ray ◽  
Fe Species

Abstract. Atmospheric iron (Fe) can be a significant source of nutrition for phytoplankton inhabiting remote oceans, which in turn has a large influence on the Earth's climate. The bioavailability of Fe in aerosols depends mainly on the fraction of soluble Fe (= [FeSol]/[FeTotal], where [FeSol] and [FeTotal] are the atmospheric concentrations of soluble and total Fe, respectively). However, the numerous factors affecting the soluble Fe fraction have not been fully understood. In this study, the Fe species, chemical composition, and soluble Fe concentrations in aerosols collected in Tsukuba, Japan were investigated over a year (nine samples from December 2002 to October 2003) to identify the factors affecting the amount of soluble Fe supplied into the ocean. The soluble Fe concentration in aerosols is correlated with those of sulfate and oxalate originated from anthropogenic sources, suggesting that soluble Fe is mainly derived from anthropogenic sources. Moreover, the soluble Fe concentration is also correlated with the enrichment factors of vanadium and nickel emitted by fossil fuel combustion. These results suggest that the degree of Fe dissolution is influenced by the magnitude of anthropogenic activity, such as fossil fuel combustion. X-ray absorption fine structure (XAFS) spectroscopy was performed in order to identify the Fe species in aerosols. Fitting of XAFS spectra coupled with micro X-ray fluorescence analysis (μ-XRF) showed the main Fe species in aerosols in Tsukuba to be illite, ferrihydrite, hornblende, and Fe(III) sulfate. Moreover, the soluble Fe fraction in each sample measured by leaching experiments is closely correlated with the Fe(III) sulfate fraction determined by the XAFS spectrum fitting, suggesting that Fe(III) sulfate is the main soluble Fe in the ocean. Another possible factor that can control the amount of soluble Fe supplied into the ocean is the total Fe(III) concentration in the atmosphere, which was high in spring due to the high mineral dust concentrations during spring in East Asia. However, this factor does not contribute to the amount of soluble Fe to a larger degree than the effect of Fe speciation, or more strictly speaking the presence of Fe(III) sulfate. Therefore, based on these results, the most significant factor influencing the amount of soluble Fe in the North Pacific region is the concentration of anthropogenic Fe species such as Fe(III) sulfate that can be emitted from megacities in Eastern Asia.

Ultrasonic Creep Damage Detection by Frequency Analysis for Boiler Piping

2006 ◽  
Vol 129 (4) ◽  
pp. 713-718 ◽  
Author(s):  
Hiroaki Hatanaka ◽  
Nobukazu Ido ◽  
Takuya Ito ◽  
Ryota Uemichi ◽  
Minoru Tagami ◽  
...  
Keyword(s):  
Power Generation ◽  
High Temperature ◽  
Damage Detection ◽  
Fossil Fuel ◽  
Creep Damage ◽  
High Energy ◽  
Assessment Method ◽  
Nondestructive Method ◽  
Fuel Combustion ◽  
Fossil Fuel Combustion

Boiler piping of fossil-fuel combustion power generation plants are exposed to high-temperature and high-pressure environments, and failure of high-energy piping due to creep damage has been a concern. Therefore, a precise creep damage assessment method is needed. This paper proposes a nondestructive method for creep damage detection of piping in fossil-fuel combustion power generation plants by ultrasonic testing. Ultrasonic signals are transformed to signals in a frequency domain by Fourier transform, and a specific frequency band is chosen. To determine the creep damage, the spectrum intensities are calculated. Calculated intensities have a good correlation to life consumption of the weld joints, and this method is able to predict the remaining life of high-temperature piping, which has been already installed.

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